The OSUCCC Microarray Shared Resource (MASR) was established as a developing Shared Resource in 1998 with genome wide expression analysis, and subsequently became a full shared resource in 1999 offering genome wide expression analysis using Affymetrix GeneChips. In November 2004, under the direction of Dr. Cario Croce, the MASR underwent a massive expansion with an infusion of capital from the CCC's institutional resources. Dr. Croce developed and built the first microarray to study microRNAs which has now been utilized by a multitude of OSUCCC investigators, by CCC investigators from the NCI and other NCI-designated cancer centers and by investigators from around the world. In 2008, MASR acquired Agilent and Exiqon microarray platforms. The MASR has thus kept up with the dramatic expansion of demands for nucleic acid-based technologies in cancer research in order to serve CCC members with an outstanding range of expression analyses. For projects utilizing microarray technologies, MASR offers multiple unique, cost effective, and comprehensive state-of-the-art services and experience, including timely experimental design consultation, genome wide expression and SNP/mutation analysis on microarray and on next-generation instrumentation, array comparative genomic hybridization (CGH) assessment of DNA and RNA integrity, quantification of DNA and RNA, design, fabrication and validation of custom microarrays, quality sample processing, hybridization, and scanning. Microarray analysis supports studies of the diverse genetic profile of cancer including analysis of genomes, epigenomes and transcriptomes in murine and human systems including both normal and malignant tissues from cancer patients. MASR uses CAarray and trains investigators to upload results to Gene Expression Omnibus (http//www/ncbi.nim.nih.gov/geo). Through outstanding institutional support and leveraging of CCSG resources, MASR has developed into a robust centralized shared resource serving the needs of OSUCCC investigators, cancer researchers in the state of Ohio, and nationally with multiple NCI cancer centers. As predicted in our last review, regular usage of the MASR has grown by over 100%, in part the result of a $2.0 m in capital investment by the CCC into the MASR equipment using institutional support. During the past 12 months, the faculty and staff of the MASR have worked with 52 OSUCCC members coming from five of the six OSUCCC scientific programs. OSUCCC members with peer-reviewed funded accounted for 71.8% of the MASR usage; overall OSUCCC usage is 88.9%. These past 12 months indicate a continuous robust demand for MASR services and predict expanded demand for MASR services.